1. Field of the Invention
The present invention relates to an operation microscope, of the type used in an surgical operation.
2. Description of the Prior Art
This type of operation microscope consists of a tube with an objective lens attached to its end and an eyepiece tube attached to the this tube, each tube being rotatable. In such an operation microscope, to make the observational angle optimal with respect to an observation objective, the tube is frequently turned up and down in the course of operation, depending on the operational situation.
As a result of this constant turning up and down of the tube, the eyepiece tube obviously changes its position. Therefore, when the angle of turning up or down the tube is large, it becomes necessary to return the eyepiece tube to its original position, by hand i.e., angle so that the observation by an operator is easy. This problem can result in the suspension of the operation.
Moreover, there is a problem in that due to the angle adjustment for the eyepiece tube, the operator's hands, which must be maintained in a clean state become contaminated by touching the eyepiece tube.